Products of formaldehyde and myrcene and processes for making same



W. T. SOMERVILLE PRODUCTS OF FORMALDEHYDE AND MYRCENE AND April 17, 1962 PROCESSES FOR MAKING SAME 3 Sheets-Sheet 1 Filed June 2, 1960 NU UE EWFQQ E DWMEkQI Q\D Pi 'IMWTI NMNN oQow seam INVENTOR VV/luwo TSOM PV/LLE.

M ATTORNEYS April 17, 1962 w. T. SOMERVILLE PRODUCTS OF FORMALDEHYDE AND MYRCENE AND PROCESSES FOR MAKING SAME 5 Sheets-Sheet 2 Filed June 2, 1960 w w h Q 5 u a R W 1 W m N M IR w T m7 M w 4 m m April 17, 1962 w. T. SOMERVILLE PRODUCTS OF FORMALDEHYDE AND MYRCENE AND PROCESSES FOR MAKING SAME 3 Sheets-Sheet 3 Filed June 2, 1960 C) If) ow om cu United States Patent 3,030,384 Patented Apr. 17, 1962 PRODUCTS F FORMALDEHYDE AND MYRCENE AND PROCESSES FOR MAKING SAME Willard T. Somerville, Fair Haven, N.'J., assignor to International Flavor-s8: Fragrances, Inc., New York, N.Y.,

a corporation of New York .Filed JuneZ, 1960, Ser. No. 33,444 11 Claims. (Cl. 260-3451) This invention relates to products of formaldehyde and myrcene and processes for making same. Products made in accordance with my invention are useful as perfumes.

Myrcene has heretofore been heated and trioxymethylene with an acid catalyst to form resins, in accordance with the patent to Rummelsburg, No. 2,397,205. These resins are stated to be useful in textile finishes.

In Webb Patent 2,919,290, such production of resin by reaction of myrcene with formaldehyde and a catalyst is recognized. In col. 1, commencing line 35 of the Webb patent the following statement is made:

These two acylic trienes (referring to myrcene and allo-ocimene) react with formaldehyde, but their high degree of unsaturation makes them particularly susceptible to polymerization on thermal or acid treatments such as those necessary to provoke reaction of formaldehyde and terpene.

Therefore it is not satisfactory to utilize such terpenes for reaction with formaldehyde to produce acyclic alcohols of eleven carbon atoms.

Webb accordingly proposed to hydrogenate myrcene, and then to react hydrogenated myrcene with formaldehyde. By hydrogenating myrcene before treatment with formaldehyde he avoided resin formation.

The principal object of the present invention, accordingly, is to produce a series of useful unpolymerized reaction products of myrcene and formaldehyde, and to provide a simple, efiicient process for producing such unpolymerized products.

a H/ a 1 HO C R H2 Hz where one .of the symbols 'R and R is oxygen and the other is CH In other words, the formula 'given is for two isomers in which the O is at different positions on the ring at the right, as follows:

and

These isomers may be present singly, or as a mixture. Hereinafter these isomers are sometimes referred to, for brevity, as methyl pentenyl dihydropyran. I have also found that the production of this methyl pentenyl dihydropyran is accompanied by the production of acyclic primary C alcohols and their corresponding acid esters.

I have also found in accordance with my invention that I can produce these compounds by a process which comprises heating a mixture of myrcene, formaldehyde and a mild acid in proportions sufiicient to react only 1 mol of formaldehyde with 1 mol of myrcene, thus avoiding substantial resin formation. The formaldehyde is used in the form of paraforrnaldehyde. Aqueous formaldehyde or a substance producing formaldehyde under the reaction conditions herein may also be used. The mild acid may be formic, acetic, trimethyl acetic or propionic acid, or equivalent. The esters formed by these acids accordingly include the formate, acetate, propionate and trimethyl acetate.

The mixture of myrcene, formaldehyde and acid is heated and refluxed for several hours. The product is then washed with water and a mild alkali, and the resulting oil is separated and distilled to recover unreacted mycrene, and thereafter from the remainder is distilled and recovered the unpolymerized reaction products above mentioned. There is also distilled and recovered a miX- ture of C acyclic primary alcohols and mild acid esters thereof, which are subsequently separated from each other.

The reaction occurring is as follows:

Acetic acid .1oH1a-i( 2O) x 11K120 Myrcene lormal- Heat M ethyl pentenyl aldehyde dihydrop yran +GwH15CH2OH+O H CH OCCH Primary acyclic "H 011 alcohol Primary acyclic acetate The exact amount of acids, such as glacial acetic acid, and formaldehyde used to react with a fixed amount of myrcene can be varied to some extent. Since a certain amount of higher boiling products and residue is formed in the reaction, the yield of desired products can .be varied by varying the amount of acid and formaldehyde, and also the time of heating.

In this reaction it is customary'to add asmall amount of a preservative. The object of adding a preservative is to prevent the polymerization of the myrcene. The use of the preservative is not at all essential to the reaction, but is of some help. I commonly'use .Ionol, the commercial name for a preservative made by Shell Chemical Co. It is 2,6-di-tertiary butyl para ,cresol. Other preservatives inert to formaldehyde may be ,used, namely Ethyl Corp. Antioxidant 702, 4,4-methylene bis (2,6-di-tertiary butyl phenol), 2,2-methylene bis (4- methyl 6 -tertiary butyl phenol), ,4,4'-bis (2,.6-ditertiary butyl phenol), and 4,4-methylene bis (fi tertiary butyl ,ortho cresol), Antioxidant 720, Ethyl Corp.-

The following are examples of the manner in which I now prefer to practice the invention. The examples are illustrative, and the invention is not to be considered as restricted thereto except as indicated in the appended claims:

Example 1 A mixture of 4080 grams of myrcene 93% (28 mols), 600 grams paraforrnaldehyde 91% flake (18 mols) and 1600 grams of glacial acetic acid (26 mols) are refluxed for 10 hours at atmospheric pressure. The liquid temperature is 107 to 109 C. At the end of this reflux period the material is cooled to room temperature and then poured into an equal volume of water, and Washed three times with hot water and once with sodium bicarbonate solution. The separated oil was distilled over a 14" protruded packed column to a liquid temperature of 100 C., using a vacuum of 25 mm. of mercury to recover the myrcene. The remainder of the material was distilled without a column at a vacuum of 2 to 3 mm. One half percent Ionol was added before this distillation was started, as a preservative. 1,736 grams of myrcene were recovered from the first distillation, and an additional 446 grams from the distillation without a column. A fraction of desired material boiling between 68 C. and 148 C. at 3 to 5 mm. amounted to 1,237 grams. Higher boiling material amounted to 422 grams, and the residue was 317 grams.

The 1,237 grams of product, when redistilled using a fractionating column, yielded 510 grams of methyl pentenyl dihydropyran.

The pure methyl pentenyl dihydropyran separated from the reaction mixture by fractionation has the following physical constants:

B.P. 602/3.5 mm.; 5354/1,9 mm. 11 1.48101.4814 D 09159-09165 O-CH -C=C "group (chemical shift tau=5.86) shown on the magnetic resonance chart is presumed to be due to an unresolved trio of peaks,.resulting from a mixture of 4(4-methyl-3-pentenyl) 5,6-2H-pyran which would give a doublet, and 3(4-methyl-3-pentenyl), 5,6-dihydro-2H- pyran, which would give a singlet. Determination of nuclear magnetic resonance was made in accordance with the disclosure thereof contained in Applications of Nuclear Magnetic Resonance Spectroscopy, by L. M. Jackman, Pergamon Press, New York, 1959.

In addition, an alcohol-ester section of 404 grams, B.P. 73100 C./0.7-0.8 mm., n of 1.48401.4950 was obtained. This fraction had a 11 of 1.4908, a D 0.9300, and when saponified with Normal sodium hydroxide solution required 1.80 ml. After acetylation with acetic anhydride, one gram of acetylated product required 5.50 ml. of Normal sodium hydroxide for saponification. The infrared spectrum, a drawing of which is referred to below, shows both the presence of alcohol and ester groups. This spectrum represents the mixture obtained by this example. It will vary somewhat depending on the exact composition of the mixture produced.

I have also found that other organic acids, besides acetic acid, can be used in this reaction. The following is an example using propionic acid:

Example 2 3060 grams of myrcene, 93% purity, 900 grams of paraformaldehyde 91%, and 2960 grams of propionic acid (99% pure) were refluxed together for hours.

The liquid temperature was approximately 112 C.

packed column at 1 mm. to yield:

692 grams methyl pentenyl dihydropyran fraction, B.P.

287 grams primary acyclic C alcohol-propionate fraction, B.P. 83121/1 mm.

374 grams higher boiling material, B.P. 127-143'/ 1 mm.

88 grams residue Example 3 Reaction of myrcene with formaldehyde in the presence of formic acid.

In a flask, fitted with a stirrer, thermometer, reflux condensers, and heating mantle, was placed:

3060 grams of myrcene (97% pure) 2000 grams of 90% formic acid 900 grams of paraformaldehyde 91% flake 30 grams of Ionol The mixture was refluxed for 10 hours. The liquid temperature varied between and C. It was then cooled and poured into water and the separated oil washed twice with hot water and once with sodium bicarbonate solution. The material was distilled from a flask without a column in an attempt to recover myrcene, as there was very little unreacted myrcene. The material was then distilled in a vacuum of 2 to 3 mm. to yield the following fractions:

B.P. 28 to 53 C., 118 grams B.P. 53 to 67 C., 225 grams B.P. 71 to 115 C., 1026 grams (C primary acycl-i alcohol-ester section) B.P. 115 to 131 C., 513 grams (higher boiling material) Residue, 217 grams The alcohol-ester section mentioned above contains 62% ester when analyzed by saponification, assurning'a molecular weight of 194 for the formate. It analyzed 34.1% free alcohol by acetylation and correcting for the known ester content. The specific gravity at 20/20 was 0.9890; the index of refraction at 20 was 1.4909.

The 225 gram section, mentioned above, was carefully refractionated to obtain methyl pentenyl dihydropyran. Upon refractionation 58 grams of crude methyl pentenyl dihydropyran were obtained. This crude material was found to contain 30% of methyl pentenyl dihydropyran. by vapor phase chromatography.

Results of this experiment indicate that the reaction of myrcene and paraformaldehyde in the presence of formic acid is much more vigorous and more complete than the other acids. Very little or no myrcene is recovered unreacted. Also, the amount of methyl pentenyl dihydropyranformed is quite small, while the amount of alcohol-ester mixture is larger than with acetic acid.

Example 4.-Using Beta Pinene Pyrolyzate Containing About 75% of Myrcene A mixture of 4080 grams of beta pinene pyrolyzate 900 grams of paraformaldehyde (91% 2400 grams of glacial acetic acid, and 50 grams of Ionol was reacted and worked up as in Example to give cor responding fractions. fe following products were obtained:

1543 grams of recovered myrcene 525 grams methyl pentenyl dihydropyran 1053 grams of C alcohol and corresponding ester fraction 382 grams higherboiling products, and

414 grams of residue The alcohol ester fraction boiled at 70-93 C. at 1.5

mm., and had a D of 0.9584 and a refractive index at 20 of 1.4900. Upon saponfication it required 1.98 ml. of Normal sodium hydroxide solution per gram of sample.

After acetyla-tion a sample-required 5.55 ml. of Nor- :mal s d m hyd o ide o ution t s po i y a ena of acetylated product.

Example 5 .-Using Pivalic Acid (Trimethyl Acetic Acid) In this example I used:

816 grams of myrcene (96%) 1224 grams of trimethyl acetic acid 240 grams of paraformaldehyde 91% and grams of Ionol The mixture was refluxed for 10 hours, during which time the liqiud temperature varied from 115 C. at the beginning to 140 C. at the end of 10 hours. The mixture was decomposed with water and washed with very hot water, and then repeatedly washed with hot sodium bicarbonate solution until neutral. It was then vacuum distilled to yield the following products:

217 grams of recovered myrcene 5 6 grams methyl pentenyl dihydropyran 186 grams of C alcohol Example 6 .Using Aqueous Formaldehyde In this example I react a mixture of 2040 grams of myrcene (91% 1600 grams of glacial acetic acid, and 4425 grams of formaldehyde, aqueous solution (37%) This mixture was refluxed and stirred for 10 hours. It was then poured into water and the oily layer separated and washed with water and sodium bicarbonate solu tion. The crude oil was then worked up as in Example 1 to yield:

1056 grams of recovered myrcene 23 grams of methyl pentenyl dihydropyran 175 grams of C alcohols and corresponding esters, BR 62 to 72 C. at 1 mm., index of refraction at 20, 1.4869, D 0.9537

227 grams of higher boiling material, and

379 grams of residue The alcohol ester section when saponified was found to have an ester content equivalent to 0.12 ml. of Normal sodium hydroxide per gram. An examination of.

this material by infrared indicated that this material consisted principally of alcohols.

In the accompanying drawings forming part of this specification:

FIG. 3 is a nuclear magnetic resonance chart of the methyl pentenyl dihydropyran.

The methyl pentenyl dihydropyran is a perfume material having a strong refreshing floral odor with rose, muguet, violet and limey character. It is useful in a wide range of perfumes from floral to herb-cologne blends. The C alcohols are perfume materials having a very rich rose-violet note of distinctive character. The mixture of C alcohols and their esters is a perfume material having an odor somewhat reminiscent of the above mentioned alcohols, but drier and more herbaceous.

I claim:

1. Isomeric compounds singly and in admixture with one another, having theformula:

H3 CH other is CH 2. The compound having the formula:

CH3 C 3 3. The compound having the formula:

C53 /CH3 0 CH2 i t H10\ /0\ /0 C C Ha Hz 4. A process which comprises heating a mixture of myrcene, formaldehyde and a mild acid at a reaction temperature in proportions to react 1 mol of formaldehyde FIG. 1 is an infrared spectrograph of the methyl pen- I with 1 mol of myrcene without substantial formation of resin, to produce at least one of the substances having the formula CH3 CH:

/C H/CE: a t H2C\ /C\ /R' C O H, H, where one of the symbols R and R is oxygen and the other is CH 5. A process which comprises heating a mixture of myrcene, paraformaldehyde and glacial acetic acid at a reaction temperature in proportions to react 1 mol of paraformaldehyde with 1 mol of myrcene without substantial formation of resin, to produce at least one of the substances having the formula /C H/CEa F t t I o o H: H:

where one of the symbols R and R is oxygen and the other is CH 6. A process which comprises heating a mixture of myrcene, formaldehyde and a mild acid at a. reaction temperature in proportions to react 1 mol of formaldehyde with 1 mol of myrcene Without substantial formation of resin, to produce at least one of the substances having the formula CH3 CH where one of the symbols R and R is oxygen and the 9. A process in accordance with claim 6, in which the acid is propionic acid.

10. A process in accordance withclaim 6, in which the acid is trimethyl acetic acid.

5 11. A process in accordance with claim 6, in which the acid is acetic acid.

References Cited in the file of this patent UNITED STATES PATENTS 2,858,322

Kubler et al Oct. 28, 1958 2,868,805 Arth et a1 Jan. 13, 1959 2,919,290 Webb Dec. 29, 1959 OTHER REFERENCES Gresham' et al.: Jour. Am. Chem. Soc., vol. 71, pages 737-8 (1949). 

1. ISOMERIC COMPOUNDS SINGLY AND IN ADMIXTURE WITH ONE ANOTHER, HAVING THE FORMULA: 